In this work, we synthesized a new composite material comprised of previously formulated resveratrol nanobelt-like particles (ResNPs) and selenium nanoparticles (SeNPs), namely ResSeNPs. Characterization was provided by FESEM and optical microscopy, as well as by UV-Vis and FTIR spectroscopy, the last showing hydrogen bonds between ResNPs and SeNPs. DPPH, TBA, and FRAP assays showed excellent antioxidative abilities with ResNPs and SeNPs contributing mainly to lipid peroxidation inhibition and reducing/scavenging activity, respectively. The antibacterial effect against common medicinal implant colonizers pointed to notably higher activity against Staphylococcus isolates (minimal inhibitory concentrations 0.75–1.5%) compared to tested gram-negative species (Escherichia coli and Pseudomonas aeruginosa). Antibiofilm activity against S. aureus, S. epidermidis, and P. aeruginosa determined in a crystal violet assay was promising (up to 69%), but monitoring of selected biofilm-related gene expression (pelA and algD) indicated the necessity of the involvement of a larger number of genes in the analysis in order to further establish the underlying mechanism. Although biocompatibility screening showed some cytotoxicity and genotoxicity in MTT and alkaline comet assays, respectively, it is important to note that active antioxidative and antibacterial/antibiofilm concentrations were non-cytotoxic and non-genotoxic in normal MRC-5 cells. These results encourage further composite improvements and investigation in order to adapt it for specific biomedical purposes.

Background/Objectives: Acinetobacter baumannii, one of the most dangerous pathogens, is able to form biofilm structures and aggravate its treatment. For that reason, new antibiofilm agents are in need, and new sources of antibiofilm compounds are being sought from plants and their products. Cinnamon essential oil is associated with a wide spectrum of biological activities, but with a further improvement of its physicochemical properties it could provide even better bioavailability. The aim of this work was the evaluation of the antibiofilm properties of cinnamon essential oil and its emulsion. Methods: In order to evaluate the antibiofilm activity, crystal violet assay was performed to determine biofilm biomass. The main components of the biofilm matrix were measured as well as the motile capacity of the tested strains. Gene expression was monitored with RT-qPCR, while treated biofilms were observed with Raman spectroscopy. Results: A particularly strong potential against pre-formed biofilm with a decreased biomass of up to 66% was found. The effect was monitored not only with regard to the whole biofilm biomass, but also on the individual components of the biofilm matrix such as exopolysaccharides, proteins, and eDNA molecules. Protein share drops in treated biofilms demonstrated the most consistency among strains and rose to 75%. The changes in strain motility and gene expressions were investigated after the treatments were carried out. Raman spectroscopy revealed the influence of the studied compounds on chemical bond types and the components present in the biofilm matrix of the tested strains. Conclusions: The results obtained from this research are promising regarding cinnamon essential oil and its emulsion as potential antibiofilm agents, so further investigation of their activity is encouraged for their potential use in biomedical applications.

Background/Objectives: Pulmonaria officinalis L., commonly known as lungwort, is a medicinal plant traditionally used for respiratory ailments, but its biological activities have not yet been sufficiently researched. The aim of this study was to investigate the antioxidant and dose-dependent genotoxic/antigenotoxic properties of a 70% ethanolic extract. Methods: Quantification of polyphenols and GC–MS analysis were performed in order to chemically characterize the extract. Antioxidant activity was evaluated through DPPH, PFRAP, total antioxidant capacity (TAC), and ferrous ion chelating assay (FIC). MTT and alkaline comet assay were used for investigation of cytotoxicity and geno/antigenotoxicity on normal fetal fibroblast cells (MRC-5). Results: The chemical analysis of the extract showed that the extract is rich in polyphenolics and that phytol is the most abundant compound, accompanied by terpenoids, fatty acids, alcohols, polyketides, and alkaloids. In addition, notable antioxidant capacity was detected in all tests applied. The extract reduced cell viability only at the highest concentration tested (33.7%). Furthermore, a dual dose-dependent effect was recorded since the genotoxic effect of the tested extract was observed at higher concentrations, while non-genotoxic concentrations showed protective effects against oxidative damage of DNA. Namely, pretreatment with lungwort extract reduced the DNA damage induced by H₂O₂, with the highest protective effect at the lowest tested concentration, indicating a hormetic mode of action. Conclusions: These results provide a solid foundation for future research into this medicinal plant, with the aim of its potential therapeutic use in the prevention of diseases associated with oxidative stress.

Background/Objectives: Articular cartilage and osteochondral defects have limited intrinsic healing capacity. This study evaluated the biocompatibility and in vivo regenerative potential of two novel hydroxyapatite-based hydrogels — Simplex Gel (hydroxyapatite/hydroxyethyl cellulose) and Complex Gel (additionally enriched with sodium hyaluronate and chondroitin sulfate) — compared with a commercial hyaluronic-acid control (Reviscon^® 1%). Methods: Cytotoxicity (MTT assay, MRC-5 fibroblasts) and genotoxicity (alkaline comet assay, human peripheral blood lymphocytes) were assessed in vitro. In vivo, six Vietnamese pigs received a superficial chondral or a deeper osteochondral defect on the tibial condyle of the right knee, treated with Reviscon^®, Simplex Gel, or Complex Gel. After 12 weeks, sections were stained (H&E, Mallory–Azan, Picrosirius Red, PECAM-1) and analyzed stereologically (n = 15 sections/bone). Results: Both gels were non-genotoxic and only weakly to moderately cytotoxic at the two highest concentrations (ISO 10993-5). All treatments achieved complete defect filling with regenerated cartilage and bone, without necrosis, inflammation, or other pathological changes. Complex Gel produced the most pronounced regenerative response, with the highest cell numerical densities and the most intense collagen deposition. Conclusions: Both hydrogels, particularly Complex Gel, are biocompatible and support osteochondral regeneration in a large-animal knee model, warranting further preclinical development.